Mechanical apparatus and method for artificial disc replacement

ABSTRACT

The present invention relates to a device and method which may be used to reinforce the native annulus during spinal surgery. The device is a catheter based device which is placed into the inter-vertebral space following discectomy performed by either traditional surgical or endoscopic approaches. The distal end of the catheter is comprised of an expansile loop which may be increased in diameter by advancement of a portion of the catheter via its proximal end, such proximal end remaining external to the body. The expansile loop may be formed such that when the loop is diametrically contracted the loop feeds into its other end, similar to a snake eating its own tail. Stabilization of the outer portion of the loop and pulling out the inner portion will thereby increase the overall diameter of the loop while maintaining it as a closed loop or torus. The expansile loop then uses an attachment means to secure it to substantially healthy tissues of the annulus, nucleus, or endplates. The present invention comprises four embodiments and can be used to 1) facilitate disk fusing, 2) perform an artificial replacement of the nucleus, 3) perform an artificial replacement of the annulus, or 4, perform an artificial replacement of both the nucleus and annulus.

CROSS-REFERENCES

The present application is a continuation-in-part of patent applicationSer. No. 11/153,776 filed on Jun. 15, 2005 and Ser. No. 11/173,034 filedon Jul. 1, 2005 now U.S. Pat. No. 7,442,210. These applications areincorporated herein by this reference.

FIELD OF THE INVENTION

The present invention generally relates to devices and methods for therepair of inter-vertebral discs. More, specifically, the presentinvention relates to devices and methods for the treatment of spinaldisorders associated with the nucleus, annulus and inter-vertebral disc.

BACKGROUND OF THE INVENTION

Inter-vertebral disc disease is a major worldwide health problem. In theUnited States alone almost 700,000 spine procedures are performed eachyear and the total cost of treatment of back pain exceeds $30 billion.Age related changes in the disc include diminished water content in thenucleus and increased collagen content by the 4^(th) decade of life.Loss of water binding by the nucleus results in more compressive loadingof the annulus. This renders the annulus more susceptible todelamination and damage. Damage to the annulus, in turn, acceleratesdisc degeneration and degeneration of surrounding tissues such as thefacet joints.

The two most common spinal surgical procedures performed are discectomyand spinal fusion. These procedures only address the symptom of lowerback pain. Both procedures actually worsen the overall condition of theaffected disc and the adjacent discs. A better solution would beimplantation of an artificial disc for treatment of the lower back painand to restore the normal anatomy and function of the diseased disc.

The concept of a disc prosthesis dates back to a French patent by vanSteenbrugghe in 1956. 17 years later, Urbaniak reported the first discprosthesis implanted in animals. Since this time, numerous prior artdevises for disc replacement have been proposed and tested. These aregenerally divided into devices for artificial total disc replacement orartificial nucleus replacement. The devises proposed for artificialtotal disc replacement, such as those developed by Kostuik, thatgenerally involve some flexible central component attached to metallicendplates which may be affixed to the adjacent vertebrae. The flexiblecomponent may be in the form of a spring or alternatively a polyethylenecore (Marnay). The most widely implanted total artificial disc to dateis the Link SB Charite disc which is composed of a biconvex ultra highmolecular weight polyethylene spacer interfaced with two endplates madeof cobalt-chromium-molybdenum alloy. Over 2000 of these have beenimplanted with good results. However device failure has been reportedalong with dislocation and migration. The Charite disc also requires anextensive surgical dissection via an anterior approach.

The approach of artificial nucleus replacement has several obviousadvantages over artificial total disc replacement. By replacing only thenucleus, it preserves the remaining disc structures such as the annulusand endplates and preserves their function. Because the annulus andendplates are left intact, the surgical procedure is much simpler andoperative time is less. Several nuclear prostheses can be place via aminimally invasive endoscopic approach. The nucleus implant in widestuse today is the one developed by Raymedica (Bloomington, Minn.) whichconsists of a hydrogel core constrained in a woven polyethylene jacket.The pellet shaped hydrogel core is compressed and dehydrated to minimizesize prior to placement. Upon implantation the hydrogel begins to absorbfluid and expand. The flexible but inelastic jacket permits the hydrogelto deform and reform in response to compressive forces yet constrain thehorizontal and vertical expansion (see U.S. Pat. Nos. 4,904,260 and4,772,287 to Ray). Other types of nuclear replacement have beendescribed which include either an expansive hydrogel or polymer toprovide for disc separation and relieve compressive load on the otherdisc components (see U.S. Pat. No. 5,192,326 to Boa). Major limitationsof nuclear prostheses are that they can only be used in patients in whomdisc degeneration is at an early stage because they require the presenceof a competent natural annulus. In discs at later stages of degenerationthe annulus is often torn, flattened and/or delaminated and may not bestrong enough to provide the needed constraint. Additionally, placementof the artificial nucleus often requires access through the annulus.This leaves behind a defect in the annulus through which the artificialnucleus may eventually extrude compressing adjacent structures. What isclearly needed is a replacement or reinforcement for the natural annuluswhich may be used in conjunction with these various nuclear replacementdevices.

Several annular repair or reinforcement devices have been previouslydescribed. These include the annulus reinforcing band described by U.S.Pat. No. 6,712,853 to Kuslich, which describes an expansile bandpressurized with bone graft material or like, expanding the band. U.S.Pat. No. 6,883,520 B2 to Lambrecht et al, describes a device and methodfor constraining a disc herniation utilizing an anchor and membrane toclose the annular defect. U.S. patent application Ser. No. 10/676,868 toSlivka et al. describes a spinal disc defect repair method. U.S. Pat.No. 6,806,595 B2 to Keith et al. describes disc reinforcement byimplantation of reinforcement members around the annulus of the disc.U.S. Pat. No. 6,592,625 B2 to Cauthen describes a collapsible patch putthrough an aperture in the sub-annular space. U.S. patent applicationSer. No. 10/873,899 to Milbocker et al. describes injection of in situpolymerizing fluid for repair of a weakened annulus fibrosis orreplacement or augmentation of the disc nucleus.

Each of these prior art references describes devices or methods utilizedfor repair of at least a portion of the diseased annulus. What isclearly needed is an improved spinal disc device and method capable ofreinforcing the entire annulus circumferentially. In addition what isclearly needed is a spinal disc device and method which may be easilyplaced into the inter-vertebral space and made to conform to this space.What is clearly needed is an improved spinal disc device and methodcapable of reinforcing the entire annulus that may be utilized either inconjunction with an artificial nucleus pulposis or may be used as areinforcement for the annulus fibrosis and as an artificial nucleuspulposis.

SUMMARY OF THE INVENTION

The present invention addresses this need by providing improved spinaldisc device and methods for the treatment of inter-vertebral discdisease. The improved device and methods of the present inventionspecifically address disc related pain but may have other significantapplications not specifically mentioned herein. For purposes ofillustration only, and without limitation, the present invention isdiscussed in detail with reference to the treatment of damaged discs ofthe adult human spinal column.

As will become apparent from the following detailed description, theimproved spinal disc device and methods of the present invention mayreduce if not eliminate back pain while maintaining near normalanatomical motion. The present invention relates to devices and methodswhich may be used to reinforce or replace the native annulus, replacethe native nucleus, replace both the annulus and nucleus or facilitatefusion of adjacent vertebrae. The devices of the present invention areparticularly well suited for minimally invasive methods of implantation.

The spinal disc device is a catheter based device which is placed intothe inter-vertebral space following discectomy performed by eithertraditional surgical or endoscopic approaches. The distal end of thecatheter is comprised of an expansile loop or mesh which may beincreased in diameter by either advancement or retraction of a controlelement comprising a flexible portion of the catheter which may bemanipulated by its proximal end, such proximal end remaining external tothe body. The expansile loop or mesh may be formed of a woven, knittedor braided material and may be made of Nylon, Dacron, syntheticpolyamide, expanded polytetrafluoroethylene (e-PTFE), polyethylene andultra-high molecular weight fibers of polyethylene (UHMWPE) commerciallyavailable as Spectra™ or Dyneema™, as well as other high tensilestrength materials such as Vectran™, Kevlar™, natural or artificiallyproduced silk and commercially available suture materials used in avariety of surgical procedures. Alternatively the expansile loop or meshportion of the catheter may be made of a biodegradable or bioabsorbablematerial such as resorbable collagen, LPLA (poly(l-lactide)), DLPLA(poly(dl-lactide)), LPLA-DLPLA, PGA (polyglycolide), PGA-LPLA orPGA-DLPLA, polylactic acid and polyglycolic acid which is broken downand bioabsorbed by the patient over a period of time. Alternatively theexpansile portion of the catheter may be formed from metallic materials,for example, stainless steel, elgiloy, Nitinol, or other biocompatiblemetals. Further, it is anticipated that the expansile loop portion ofthe device could be made from a flattened tubular knit, weave, mesh orfoam structure.

The expansile loop may be formed such that when the loop isdiametrically contracted one end of the loop feeds into its other end,similar to a snake eating its own tail. Alternatively, the expansileloop may be formed such that when it is diametrically contracted it isin the shape of a toroid invaginating into itself. Stabilization of theouter portion of the loop and pulling out the inner portion will therebyincrease the overall diameter of the loop while maintaining it as asubstantially closed loop or toroid.

In one embodiment, the present invention consists of a device andmethod, whereby the present invention is first delivered and expandedwithin the vertebral space to the limits of the inner portion of thenative annulus to reinforce or artificially replace the native annulus.

In another embodiment, the present invention consists of a device andmethod, whereby the present invention is first delivered and expandedwithin the vertebral space to the limits of the inner portion of thenative annulus and then an injection of polymeric or hydrogel or likematerial is conducted to reinforce or artificially replace the nativeannulus.

In another embodiment, the present invention consists of a device andmethod, whereby the present invention is first delivered and expandedwithin the vertebral space to the limits of the inner portion of thenative annulus and then the inner portion of the present invention iscentrally expanded to the limits of an artificial nucleus concurrentlyor previously placed within the inter-vertebral space.

In another embodiment, the present invention consists of a device andmethod, whereby the present invention is first delivered within thevertebral space and into the area of the nucleus, which may have beenpreviously removed, and expanded to the limits of the outer portion ofthe area of the native nucleus and then injected with a polymer orhydrogel or like material conducted to reinforce or artificially replacethe native nucleus.

In another embodiment, the present invention consists of a device andmethod, whereby the present invention is first delivered within thevertebral space and expanded within the vertebral space to the limits ofthe outer portion of the native annulus and then an injection ofpolymeric or hydrogel material is conducted to reinforce or artificiallyreplace the native annulus. Then the present invention is delivered intothe nucleus area and expanded to the limits of the outer portion of thenative nucleus or an artificial nucleus concurrently placed and then aninjection of polymeric or hydrogel material is conducted to reinforce orartificially replace or reinforce the nucleus.

In another embodiment, the present invention consists of a device andmethod, whereby the present invention is first delivered and expandedwithin the vertebral space and expanded inward from the outer limits ofthe annulus to the point where essentially no central hole remains inthe toroid and a polymeric or hydrogel or like material is injected intothe expanded mesh.

In another embodiment, the present invention consists of a device andmethod, whereby the present invention is delivered and expanded withinthe vertebral space and then an injection of a bone graft material,polymeric bone graft compound, or material inducing or promoting thegrowth of bone such as, but not limited to growth factors, BMP or likeis conducted in order to facilitate the fusion of an adjacent vertebrae.

The present invention and variations of its embodiments is summarizedherein. Additional details of the present invention and embodiments ofthe present invention may be found in the Detailed Description of thePreferred Embodiments and Claims below. These and other features,aspects and advantages of the present invention will become betterunderstood with reference to the following descriptions and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-section view of one embodiment of the presentinvention with the control element attached to the interior distal endof the expansile loop and in a contracted delivery configuration.

FIG. 2 is a cross-sectional of one embodiment of the present inventionwith the control element attached to the interior distal end of theexpansile loop and with the sheath retracted and the expansile loopexposed.

FIG. 3 is a cross-section view of one embodiment of the presentinvention with the control element attached to the interior distal endof the expansile loop and with the expansile in an expandedconfiguration.

FIG. 4 is a cross-section of the one embodiment of the present inventionwith the control element attached to the interior distal end of theexpansile loop and with the expansile loop in an expanded and the innercircumference of the expansile loop in a contracted configuration.

FIG. 5 is a magnified cross-section view from FIG. 4 of the presentinvention with the control element attached to the interior distal endof the expansile loop and showing the controlling end of the expansileloop.

FIG. 6 is a cross-section view of another embodiment of the presentinvention with the control element exiting the sidewall of the outersection of the expansile loop and releasably connecting to the proximalportion of the outer section of the expansile loop and with theexpansile loop shown in a contracted delivery configuration.

FIG. 7 is a cross-sectional view of another embodiment of the presentinvention with the sheath retracted and the expansile loop exposed.

FIG. 8 is a cross-section view of the embodiment of FIG. 1 with theexpansile loop in an expanded configuration.

FIG. 9 is a magnified cross-section view from FIG. 8 of the presentinvention showing the controlling end of the expansile loop.

FIG. 10 is a cross-section view of another embodiment of the presentinvention with two control elements and in a contracted deliveryconfiguration.

FIG. 11 is a cross-sectional of another embodiment of the presentinvention with two control elements and with the sheath retracted andthe expansile loop exposed.

FIG. 12 is a cross-section view of another embodiment of the presentinvention with two control elements and with the expansile loop in anexpanded configuration.

FIG. 13 is a cross-section of another embodiment of the presentinvention with two control elements and with the expansile loop in anexpanded and the inner circumference of the expansile loop in acontracted configuration.

FIG. 14 is top view cross-section view of a spinal body (vertebrae)showing the posterolateral access tube advanced into the inter-vertebralspace.

FIG. 15 is a top view cross-section view of a spinal body (vertebrae)with one of the embodiments of the present invention being positionedwithin the inter-vertebral space of the spinal body (vertebrae).

FIG. 16 is a top view cross-section of a spinal body (vertebrae) withone of the embodiments of the present invention expanded and surroundingthe nucleus section of the spinal body (vertebrae).

FIG. 17 is top view cross-section of a spinal body (vertebrae) with oneof the embodiments of the present invention's outside diameter expandedand the inside diameter contracted within the inter-vertebral space ofthe spinal body (vertebrae).

FIG. 18 is a cross-section dimensional view of the expansile loop in apartially expanded configuration with a diameter D and a height H.

FIG. 19 is a cross-sectional dimensional view of the expansile loop inan expanded configuration with the diameter increasing +D and the heightincreasing +H.

FIG. 20 is a cross-section view of another embodiment of the presentinvention with the expansile loop in an invaginated configuration(whereby a portion of the expansile loop is bent back and enteringitself) with the expansile loop in a partially expanded configuration.

FIG. 21 is a cross-sectional view of additional feature of the presentinvention with an inner catheter or control element having a pluralityof holes for delivery and injection of biomaterials.

FIG. 22 is a perspective view of an element of the present inventionwhereby locking elements on the distal end of the expansile interiorloop are engaged to the expansile outer loop.

FIG. 23 is a cross sectional view of the attachment means in the from ofa suture and demonstrating a suture delivery system already advancedthrough an access tube and utilizing non-absorbable or re-absorbablesutures to attach the contracted configuration of the expansile mesh tothe inner wall of the annulus at multiple points.

FIG. 24 shows a cross sectional view of the attachment means in the formof a staple or helicoil with a delivery system already advanced throughthe access tube and utilizing non-absorbable or re-absorbable stables orhelicoil mechanism to secure the expanded expansile mesh to the innerwall of the annulus at multiple points. Also shown are non-absorbable orre-absorbable stables or helicoils used to attach the expanded expansilemesh to the outer wall of an artificial nucleus at multiple points.

FIG. 25 shows a cross sectional view of the expansile mesh containedwithin a vertebral bone structure with the mesh attached to the bonestructure by means of screws or anchors.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

One embodiment 10, 11 of the spinal disc device, as shown in FIGS. 1-5,consists of an elongated probe 15, with a proximal end 17 and a distalend 16. Referring to FIGS. 1 and 2, is can be seen that the elongatedprobe 15 is constructed from at least two elements, a flexible innercatheter control element 19, and a stiffer outer catheter element 12.The inner catheter control element 19 is slidably located within theouter catheter element 12. At the proximal end 17 of elongated probe 15,the inner catheter control element 19 exits from the outer catheterelement 12, and can be advanced or retracted causing the distal end 20of the inner catheter control element 19 to move in or out of the distalend 13 of the outer catheter element 12. Near the distal end 16 of theelongated probe 15, is situated an expansile, braided or woven tubularloop 24 in a contracted or delivery configuration (FIG. 1). The innercatheter control element 19 enters the expansile loop 24 near the distalend 13 of the outer catheter element 12 and slidably resides within theexpansile loop 24. The distal end 22 of the expansile loop 24 is fedinto the proximal end 23, of the expansile loop 24 in a manner similarto a snake eating its own tail. This results in an expansile loop 24with an inner section and outer section as shown in FIGS. 1 and 2. Acovering retractable sheath 18 is placed over the elongated probe 15 tohold it in a constrained condition for delivery into the vertebral disc.After the sheath 18 is retracted, the expansile loop 24 may be increasedin circumferential diameter by withdrawing the distal end 22 of theexpansile loop 24 from the proximal end 23 of the outer expansile loop24 (FIG. 3). In this configuration, a substantially continuous interiorchamber 28 is now defined within the expanded expansile loop 25. Theouter catheter element 12 terminates at its distal end 13 and isremovably attached to the proximal end 23 of the outer section of theexpanded expansile loop 25. The inner catheter control element 19, inthe form of a filament, guidewire or flexible tube, slidably extendsfrom the proximal end 17 of the catheter or probe 15, through the outercatheter element 12, and exiting the outer catheter element at itsdistal end 13. The inner catheter element then enters the inside of theouter section of the expansile loop at its proximal end 23. The innercatheter control element 19 may be looped one, less than one, or morethan one time within the expansile loop 24, 25 between the inner andouter portions of the loop prior to the inner catheter element 19 orcontrol element terminating within the expansile loop 24, 25 at itsdistal end 22, 26. The inner catheter control element 19 is thenattached to the expansile loop 24, 25 at the distal end 22, 26 of theinner section of the expansile loop 24, 25.

The inner catheter control element can be made of a flexible yetlongitudinally incompressible material such as, but not limited to, astainless steel or Nitinol wire of 0.010″-0.040″ diameter. Slidablyadvancing the inner catheter element 19 through the outer catheterelement 12 while holding the proximal portion of the outer section ofthe expansile loop 23, 27 in place will result in the inner section ofthe expansile loop 24, 25 pulling out of the outer section of theexpansile loop 24, 25. This will result in the overall diametricexpansion of the expansile loop 24, 25. As shown in FIG. 4, onceexpansion of the outer circumference of the expansile loop 25 isachieved and fixed, pulling out the inner catheter control element 19while holding the outer section 27 of the expansile loop 25 fixed,contracts the inner circumference of the expansile loop 25 whileexpanding its height. Expansion of the expansile loop 25 into thevertebral space is achieved by the spring nature of the expansile loop's24, 25 material construction or by advancing the inner catheter controlelement 19 while holding the proximal outer section of the expansileloop 23 fixed. Next, pulling on the inner catheter control element 19while holding the proximal outer section 27 of the expansile loop 25fixed, the interior circumference of the expansile loop 25 contractstoward the center of the expansile loop 25 while the height of theexpansile loop 25 increases.

FIG. 5 is a magnified cross-section view from FIG. 4 of this presentinvention embodiment with the control element attached to the interiordistal end 26 of the expansile loop 25. This Figure shows thecontrolling end of the expansile loop 25 and the physical relationshipbetween the distal end 20 of the inner catheter 19, distal 26 andproximal end 27 of the expansile loop 25, and outer catheter element 12.

The outer catheter element 12 used for delivery of the expansile loop 24should be sufficiently stiff to allow retraction of the inner cathetercontrol element 19 without collapse or kinking. The inner cathetercontrol element 19 must be sufficiently flexible to circle around theexpansile loop 24 and attains a relatively small radius without kinkingyet have sufficient tensile strength to resist breakage when pulled fromits proximal sections. The outer catheter element 12 can be fabricatedfrom polymeric materials including, but not limited to, Nylon, Dacron,synthetic polyamide, expanded polytetrafluoroethylene (e-PTFE),polyethylene and ultra-high molecular weight fibers of polyethylene(UHMWPE), or metallic materials, including but not limited to, stainlesssteel, cobalt-chrome alloy, titanium, titanium alloy, or nickel-titaniumshape memory alloys, among others that have sufficient kink resistanceand tensile strength. The inner catheter control element 19 can bemanufactured from Nylon, Dacron, synthetic polyamide, expandedpolytetrafluoroethylene (e-PTFE), polyethylene and ultra-high molecularweight fibers of polyethylene (UHMWPE) or from metallic materialsincluding, but not limited to, stainless steel, cobalt-chrome alloy,titanium, titanium alloy, or nickel-titanium shape memory alloys, amongothers. The elements manufactured from metallic materials have adiameter from 0.001″ to 0.020″ and preferably from 0.004″ to 0.010″. Theelements manufactured from polymeric materials have a diameter from0.005″ to 0.040″ and a preferred diameter from 0.010″ to 0.020″.

The expansile loop 24, 25 is fabricated as a knit, weave or braid andcan be constructed from non-degradable materials. Suitablenon-degradable materials for the expansile loop 24, 25, include, but arenot limited to, Nylon, Dacron, synthetic polyamide, expandedpolytetrafluoroethylene (e-PTFE), polyethylene and ultra-high molecularweight fibers of polyethylene (UHMWPE) commercially available asSpectra™ or Dyneema™, as well as other high tensile strength materialssuch as Vectran™, Kevlar™, natural or artificially produced silk andcommercially available suture materials used in a variety of surgicalprocedures. The expansile loop 24, 25 fabricated as a weave or braid andcan be constructed from biodegradable or bioabsorbable materials.Suitable biodegradable and bioabsorbable materials for the expansileloop 24, 25 include, but are not limited to, resorbable collagen, LPLA(poly(l-lactide)), DLPLA (poly(dl-lactide)), LPLA-DLPLA, PGA(polyglycolide), PGA-LPLA or PGA-DLPLA, and biodegradable sutures madefrom polylactic acid and polyglycolic acid.

In addition, for some embodiments, suitable metallic materials for theexpansile loop 24, 25 may be used that include, but are not limited to,stainless steel, cobalt-chrome alloy, titanium, titanium alloy, ornickel-titanium shape memory alloys, among others. It is furthercontemplated that the metallic mesh can be interwoven withnon-resorbable polymers such as nylon fibers, carbon fibers andpolyethylene fibers, among others, to form a metal-polymer compositeweave. Further examples of suitable non-resorbable materials includeDACRON and GORE-TEX. One feature of the expansile loop 24, 25 is that itneeds to have pore sizes or openings that are small enough to hold thefilling material or nucleus from extruding out and large enough tomaintain flexibility and expansion characteristics.

In another embodiment the distal end 13 of the outer catheter element 12resides around the inner catheter control element 19. The outer catheterelement 12 is held in a constant relationship or releasably affixed tothe proximal end 23 of the outer section of the expansile loop 24. Inthis embodiment the inner catheter control element 19 is in the form ofa very flexible element which enters the proximal opening in the outsidesection of the expansile loop 23, loops one, less than one or more thanone time around the inside of the outside section of the expansile loop24 and terminates attaching at the distal end 22 of the inside sectionof the expansile loop 24. The direction of rotation of the flexiblecontrol element 19 (measured from distal end of the control element 20to the proximal end 21 is in the opposite rotational direction as thedirection of rotation of the inside section of the expansile loop 24, asit enters and loops around the outside section of the expansile loop 24.Upon retraction of the proximal end 21 of the inner catheter controlelement 19, back out of the outer catheter element 12, the distal end 13of the outer catheter element 12 stabilizes and holds the outer section23 of the expansile loop 24 in place while the inner section 22 of theexpansile loop 24 is pulled out of the outer section, resulting in anincrease in the diameter of the expansile loop 24. Once the expandedexpansile loop 25 has reached its maximum diameter, determined either bythe confines of the space into which it is expanding or by the exitpoint of the control filament through the proximal end 27 of theexpanded expansile loop 25, continued retraction of the inner cathetercontrol element 19 will result in the inner catheter control element 19producing tension on the inner circumference of the expanded expansileloop 25. The inner circumference of the expanded expansile loop 25 willcontract towards the middle of the expanded expansile loop 25 and theexpanded expansile loop's 25 height will increase. Due to the woven orbraided nature of the tubular expansile loop 24, 25, the expandedexpansile loop 25, will remain generally in the shape of a toroid bothupon its circumferential expansion and its central contraction.

An additional embodiment 39, 40 of the expansile loop device used forrepair or replacement of the annulus fibrosis of the spine can beunderstood by referring to FIGS. 6-9. As shown in FIGS. 6-8, the innercatheter control element 19 is looped around and exits through the wallof the outer section of the expansile braided loop 24 near theattachment of the outer catheter element 12 to the proximal end 23 ofthe outer section of the expansile loop 24. The inner catheter controlelement 19 is then affixed to the outer catheter element 12, at thispoint using either a knot or a releasable or removable junction orpasses proximally through the outer catheter element 12. A coveringretractable sheath 18 is placed over the elongated probe 15 to hold itin a constrained condition for delivery into the vertebral disc. Afterthe sheath 18 is retracted, a “snare” or loop is formed by the proximalportion of the inner catheter control element 19 being slidably locatedwithin the outer catheter element 12 and the expansile loop 24. If theinner catheter control element 19 is of sufficient stiffness, forexample but not limited to, a metallic guidewire of 0.010″-0.040″diameter, the snare and the expansile loop 24 may be opened by advancingthe proximal portion 21 of the inner catheter control element 19 whileholding the outer catheter element 12 and the proximal end of theexpansile loop 23 in place. This opening of the circumference of thesnare formed by the inner catheter control element 19 will result in anexpansion of the circumference of the expansile loop 24 as the innerportion of the expansile loop 24 pulls out of its outer portion. Oncethe limits of expansion of the expanded expansile loop 25 have beenreached, the inner catheter control element 19 may be detached at thejunction or connection of the outer catheter 12 and the proximal end ofthe expanded expansile loop 27 and slidably retracted out of theexpanded expansile loop 25 leaving behind a circumferentially expandedexpansile loop 25.

In an alternative embodiment of the present invention for annular repairor replacement, the inner catheter control element 19 is run inside ofthe expansile loop 24, 25 which is looped and exits first the distal endof the inner section of the braided loop 22, 26 and then exits throughthe wall of the outer portion of the braided loop 23, 27 prior to itsattachment to outer catheter element 12. The inner catheter controlelement or filament 19 may make one, less than one or more than one loopinside of the expansile loop 24, 25 prior to exiting and attaching tocatheter element 12. In this manner the inner catheter control element19 forms a “snare” or loop of one or multiple turns. If the innercatheter control element 19 is of sufficient stiffness, for example butnot limited to, a metallic guidewire of 0.010″-0.040″ diameter, thesnare may be opened by advancing the proximal portion of the innercatheter control element 21 while holding the outer catheter element 12and proximal end of the expansile loop 23, 27 in place. This opening ofthe circumference of one or more loops of the snare formed by the innercatheter control element 19 will result in an expansion of thecircumference of the expansile loop 24, 25 as the inner portion of theexpansile loop 24, 25 pulls out of its outer portion. Once the limits ofexpansion of the expansile loop 24, 25 have been reached, the innercatheter control element 19 may be pulled back into the catheter element12 by pulling on its proximal portion 21. This causes one or more loopsof the snare becoming smaller pulling on the inner circumference of theexpanded expansile loop 25 resulting in a contraction of the centralspace in the middle of the expanded expansile loop 25. Due to the wovenor braided nature of the expansile loop 24, 25, the expansile loop 24,25, will remain generally in the shape of a toroid both upon itscircumferential expansion and its central contraction.

As shown in FIGS. 10-13, another embodiment 43, 44 of the presentinvention comprises an elongated probe 15, with a proximal end 17 and adistal end 16. Referring to FIGS. 10 and 11, a first inner cathetercontrol element 19 is slidably located within the outer catheter element12. At the proximal end 17 of elongated probe 15, the inner cathetercontrol element 19 exits from the outer catheter element 12, and can beadvanced or retracted causing the distal end 20 of the inner cathetercontrol element 19 to move in or out of the distal end 13 of the outercatheter element 12. The first inner catheter control element 19, in theform of a filament, guidewire or flexible tube, slidably extends fromthe proximal end 17 of the probe 15, through the lumen of the outercatheter element 12, and exiting the outer catheter element 12 at itsdistal end 13. The inner catheter control element 19 then enters theinside of the outer section of the expansile loop 24 at its proximal end23. The inner catheter control element 19 may be looped one, less thanone, or more than one time within the expansile loop 24 between theinner and outer portions of the expansile loop 24 prior to the innercatheter element or control element 19 terminating within the expansileloop 24. The inner catheter control element 19 is then attached to theexpansile loop 24 at its distal end 22. This embodiment also includes asecond inner catheter control element 52 which extends from the proximalend 17 of the catheter or probe 15, through the outer catheter element12, and exiting the outer catheter element 12 at its distal end 13. Thesecond inner catheter control element 52 then enters the outside of theouter section of the expansile loop 24 and is attached to the distal end22 of the expansile loop 24. A covering retractable sheath 18 is placedover the elongated probe 15 to hold it in a constrained condition fordelivery into the vertebral disc. After the sheath 18 is retracted, thesecond interior catheter control element 52 is pulled back into theouter catheter control element 12 by pulling on its proximal end. Thiscauses the distal end of the expansile loop 22 to be pulled from insidethe outer portion of the expansile loop 24 expanding the outercircumference of the expansile loop 24 (See FIG. 12). Now referring toFIG. 13, the first inner catheter control element 19 may be pulled backinto the outer catheter element 12 by pulling on its proximal end. Thiswill result in a pulling in of the center of the expansile loop 25towards the middle of the loop and contraction of central space in themiddle of the expansile loop 25. Due to the woven or braided nature ofthe tubular expansile loop 24, 25, the expansile loop 24, 25, willremain generally in the shape of a toroid both upon its circumferentialexpansion and its central contraction.

In another embodiment 59, 60 as represented in FIGS. 18-20, thecontracted configuration of the expansile loop 58 comprises an expansileloop 58 which has a portion folding back into itself or invaginated 56(see FIG. 20). This forms a complete toroid with a portion invaginatedto form a diametrically contracted toroid with an inner section and anouter section that are continuous with each other. Pulling on the innercatheter control element 19 in the manner previously described willfunction to increase the diameter (+D) and increase the height (+H) ofthe expanded expansile loop 25 as the central portion of the toroid ispulled towards the center.

The entire expansile loop assembly 10 including the circumferentiallycontracted braided expansile loop 24, and inner catheter control element19, may now be compressed into the distal outer catheter element, asheath 18 or alternatively into an access tube 38 of approximately 3-20mm diameter for ease of placement. The access tube 38 may be formed fromany suitable material, as the present invention is not limited in thisrespect. Thus, the access tube 38 may be formed from a plastic material,such as a polycarbonate, or a metal material, such as stainless steel,or any suitable combination of materials. In addition, theposterolateral access tube 38 may be formed of a material that can bereadily sterilized. Further, the elongated probe 15 may be formed as asingle use device such that resterilization is not required after use.The posterolateral access tube 38 gains access to the vertebraegenerally using a posterior approach (FIG. 14).

As shown in FIG. 15, the posterolateral access tube 38 has gained accessto the vertebrae 32, having a spinal cord 33, an annulus 36 and anucleus area 34. Once in proper position in the vertebrae 32 of apatient, the expansile loop 24 may be ejected into the nucleus area 33or the annulus area (not shown in this Figure) from the distal end ofthe outer catheter element 13, sheath 18 or access tube 38 by retractingthe outer catheter element 12 or sheath 18 and simultaneously holdingthe inner catheter 19 and expansile loop 24 in a fixed position.Alternatively, an additional “pusher” element (not shown) can beadvanced distally into the outer catheter element 12 or sheath 18 oraccess tube and eject the expansile loop 24, catheter element 12 and thedistal inner catheter control element 20 from the end of the sheath 18.As previously described in the embodiments above, the expansile loop 24may now be circumferentially expanded by either pulling on or pushingthe inner catheter control element 19 in the manner described above.Furthermore, if it is desired that the central portion of the braidedexpansile loop 24 become circumferentially contracted, pulling on theinner catheter control element 19 as described above will accomplishthis feature.

Now referring the FIG. 16, the expanded expansile loop 25 achieves thedesired outer circumferentially expanded and inner circumferentiallycontracted size 48, when the inner catheter control element 19 is lockedor tied in place with a knot. This can also be accomplished by a lockingjunction located at the outer catheter element 12. The distal portions20 of the external inner catheter control element 19 can now bedisconnected or cut from a connector or proximal to the knot. Theconnector or knot is also separated from the distal outer catheterelement 12. This then leaves an outer circumferentially expanded andinner circumferentially contracted expansile loop 25 in place as aclosed loop in the desired location (shown in FIG. 16 expanded with thenucleus area 34) within the inter-vertebral space.

As represented in FIG. 21 an additional feature of the present inventionwith an inner catheter control element 41 having a plurality of distalholes 42 for delivery and injection of biomaterials which can beutilized with the embodiments of the present invention. The innercatheter control element 41 with holes 42 comprises a tubular structurewith a central lumen from the proximal end 17 of the outer catheterelement 12 communicating with side holes in the distal end 13. Theproximal end of the inner catheter or control element may be fitted withan injection device (e.g. syringe). The inner catheter control element41 is contained within the continuous interior chamber of the expandedexpansile loop 58. The holes 42 in the inner catheter control element 41are designed to be only within the continuous inner chamber.Furthermore, it is anticipated that the holes can be of different sizealong the length of the inner catheter control element to equalizebiocompatible material delivery (e.g. larger holes at the distal end,smaller holes at the proximal end). In addition, it is anticipated thatthe holes can be in various configurations, e.g. oval, or can be aplurality of slots or other similar opening.

FIG. 22 is another feature of the present invention that can be usedwith several of the embodiments 11,44,60,62 whereby non-permanentlocking elements 30 on the distal end of the expansile interior loop areengaged to the distal end 26 of the expansile outer loop. The lockingelements are extended portions of one end of the braid or loop whichinterlock with the braid or loop pattern. The locking elements functionto maintain a desired diameter of the expansile loop after expansion.

In one method of clinical use, the nucleus of the damaged disc has beenpreviously removed by discectomy techniques either through an anterior,posterior or posterolateral surgical approach. The expansile loopannular repair or replacement device 10 in its compressed configurationwithin the outer catheter element 12 or sheath 18 is advanced through anaccess tube or cannula previously placed into the inter-vertebral space.This cannula may access the inter-vertebral space from a posterior,posterolateral or anterior approach that is well known to physiciansskilled in the art. The present invention 10 is then advanced into theinter-vertebral space through the access tube 38. Once the distalexpansile loop 24 is advanced through the access tube 38 into thevertebral space it is diametrically expanded by either retraction oradvancement of the inner catheter control element 19 in the mannerpreviously described. The distal expansile loop 25 expands to the limitsof the inner portion of the remains of the native annulus and remainsdiametrically expanded and transversely contracted as illustrated inFIG. 6. Any of a number of previously described artificial nuclei puposimay then be placed in the center of the diametrically expanded expansileloop 48 either via direct visualization from the traditional surgicalapproach or via endoscope from a posterolateral approach through theforamina or form a posterior approach. These artificial nuclei may thenbe allowed to expand either through the absorption of liquids, as is thecase for hydrogel based devices, or through the injection of materialinto the nuclear prosthesis.

Once the nuclear replacement is in place, any remaining space betweenthe nuclear replacement and the expansile loop annular replacementdevice may be reduced or eliminated by centrally contracting the innercircumference of the toroid formed by the expansile loop device. This isaccomplished in the manner previously described by pulling back theinner catheter control element resulting in contraction of the innercircumference of the device until it abuts the nuclear replacement. Thebraided design of the expansile braided loop 48 will also allow it toflex and bend to conform to the inter-vertebral space. By properlyselecting the material from which the expansile braided loop isconstructed and by properly selecting the design of braid for itsmanufacture as previously described, the expansile braided loop will nowfunction as a complete circumferential support for the artificialnucleus. The expansile braided loop will prevent extrusion of theartificial nucleus through any defects in the remaining native annulusand act to stabilize the artificial nucleus during both bending andmotion of the spine and throughout the healing process. The braideddesign of the expansile loop will also permit it to flexibly bend as thecentral nucleus replacement expands and swells to its final size. Thebraided design of the expansile loop will also permit tissue in growthto occur as healing occurs. This will result in stabilization of theartificial nucleus.

In an alternative method, once the expansile braided loop 48 has beenexpanded to fill the inter-vertebral space between the artificialnucleus and the native vertebrae and remaining native annulus fibrosis,the expansile loop 48 may be filled with a suitable biologicallycompatible material. Such suitable materials that can be directlyinjected through the inner catheter control element 19 if it includes acentral lumen and openings connecting with the interior chamber of theexpansile braided loop as illustrated in FIG. 11. Alternatively, thebiocompatible materials can be injected using a separate catheterelement which can be advanced along the inner catheter control elementinto the interior chamber of the expansile braided loop. Alternatively,the biocompatible materials could be injected into the interior chamberof the expansile braided loop using a separate catheter or injectionneedle which pierces the side of the braided loop once it is expandedand in place in the inter-vertebral space. Biocompatible materials whichmay be injected include biocompatible viscoelastic materials such ashydrophilic polymers, hydrogels, homopolymer hydrogels, copolymerhydrogels, multi-polymer hydrogels, or interpenetrating hydrogels,acrylonitrile, acrylic acid, acrylamide, acrylimidine, including but notlimited to PVA, PVP, PHEMA, PNVP, polyacrylamides, poly(ethylene oxide),polyvinyl alcohol, polyacrylonitrile, and polyvinyl pyrrolidone,silicone, polyurethanes, polycarbonate-polyurethane (e.g., Corethane)other biocompatible polymers, or combinations thereof. The viscosity ofthe injected fluids must allow them to be injected either via catheteror needle into the braided expansile loop. The injected biocompatiblematerial must cure or polymerize in situ within the expansile braidedloop and within the disc space. Such in situ curing of the biocompatiblematerial may be the result of mixing of multiple components andpolymerization, temperature change in going from room to bodytemperature or elevated to body temperature, or other forms of energysuch as light or electricity applied to the injected material.

In addition, suitable materials that can be placed directed into theexpansile loop 48 and allowed to expand through the absorption ofliquids such as water include, but are not limited to, swelling hydrogelmaterials (e.g. polyacrliamide, polyacrylonitrile, polyvinyl alcohol orother biocompatible hydrogels). Examples of suitable materials for solidor semi-solid members include solid fibrous collagen or other suitablehard hydrophilic biocompatible material. The swelling of these materialsmay result in further expansion of the expansile braided loop and anincrease in the inter-vertebral disc height.

In some cases, a multiphase system may be employed, for example, acombination of solids, fluids or gels may be used. Such materials maycreate primary and secondary levels of flexibility within the braidedexpansile loop and within the vertebral disc space.

For example, the hydrogel materials (e.g. polyacrylamide,polyacrylonitrile, polyvinyl alcohol or other biocompatible hydrogels orcombinations can be dissolved in a solvent, such as dimethylsulfoxide,analogues/homologous of dimethylsulfoxide, ethanol, ethyl lactate,acetone, glycerin or combinations thereof. Small amounts of water couldalso be added to the solvent/hydrogel combination to adjust thesolutions viscosity. This solvent/hydrogel combination can be injectedinto the inter-vertebral space to replace the nucleus, the annulus, orboth the nucleus and annulus. The expansile loop 48 will assist incontaining and supporting the solvent/hydrogel combination. Afterdelivery, the solvent is replaced by bodily fluids and the hydrogelprecipitates out of solution into a hydrated solid. The solvent isadsorbed into the body tissues. Introducing an aqueous solvent, such aswater or saline, into the inter-vertebral space containing thesolvent/hydrogel combination can be performed to increase theprecipitation speed of the hydrogel. This second step facilitates theprecipitation or solidification of the hydrogel material which swellsand fills the desired inter-vertebral space.

Once the expansile loop 48 is filled with a suitable material and thematerial has cured or partially polymerized, the inner catheter controlelement or filament 19 can be withdrawn by removing its distalconnection to the junction point with the outer catheter element 12 orat its termination within the braided expansile loop and pulling theinner catheter control element out of the expansile loop. Alternatively,the inner catheter control element 19 may be cut off or disconnected atits entry point into the expansile loop. This leaves a complete toroidwithout defect, formed of the expansile loop in place to act as anannular reinforcement or replacement which may or may not surround anartificial nucleus device.

In another method of clinical use, after the braided expansile loop 48has been expanded to its maximum diametric dimension, acting as areinforcement or replacement for the damaged native annulus, the devicemay be centrally circumferentially contracted, as previously described,to fill any remaining space previously occupied by the native nucleusprior to nuclectomy. The braided expansile loop 48 expands to the limitsof the remains of disc space and the remains of the native nucleus andannulus and remains diametrically expanded and centrallycircumferentially contracted. Now the braided expansile loop area may befilled with a biomaterial or any suitable material (as described above),as the present invention is not limited in this respect. In addition tothe materials disclosed for annulus replacement, additional suitablefluid materials for nucleus and annular replacement include, but are notlimited to, various pharmaceuticals (steroids, antibiotics, tissuenecrosis factor alpha or its antagonists, analgesics); growth factors,genes or gene vectors in solution; biologic materials (hyaluronic acid,non-crosslinked collagen, fibrin, liquid fat or oils); syntheticpolymers (polyethylene glycol, liquid silicones, synthetic oils); andsaline.

Once the expansile loop is filled with a suitable material in thecentral and circumferentially contracted nuclear area and the annulararea, the inner catheter control element 19 can be withdrawn by removingits distal connection to the junction point with the outer catheterelement 12 and pulling the inner catheter control element out of theexpansile loop. Alternatively the inner catheter control element orfilament 19 may be disconnected from its attachment to the distal innerbraided expansile loop prior to its removal. Alternatively, the innercatheter control element or filament 19 may be cut off at its entrypoint into the outer section of expansile loop using a surgical tool.This leaves a complete toroid, without defect, formed of the expansileloop in place to act as an annular and nucleus reinforcement orreplacement.

In another method of clinical use, the present invention can be advancedinto the vertebral space once a nuclectomy has been performed. Once thebraided expansile loop 24 is advanced into the vertebral space, it isdiametrically expanded in the manner previously described. The braidedexpansile loop 25 expands to the limits of the out portion of theremains of the native nucleus and remains diametrically expanded andtransversely contracted. Now the braided expansile loop 48 may be filledwith a biomaterial of any suitable material, such as those previouslynoted, as the present invention is not limited in this respect. Thisinjected material is allowed to cure or polymerize to some extent, andthen the central portion of the expansile loop is circumferentiallycontracted in the manner previously described. At this point the centralnuclear area of the vertebral space is filled with the expanded mesh.This central portion can then be filled with biomaterial or any suitablematerial, such as those previously noted, as the present invention isnot limited in this respect. In addition to the materials disclosed forannulus repair or replacement, additional suitable fluid materials fornucleus replacement include, but are not limited to, variouspharmaceuticals (steroids, antibiotics, tissue necrosis factor alpha orits antagonists, analgesics); growth factors, genes or gene vectors insolution; biologic materials (hyaluronic acid, non-crosslinked collagen,fibrin, liquid fat or oils); synthetic polymers (polyethylene glycol,liquid silicones, synthetic oils); and saline.

Once the braided expansile loop is filled with a suitable material inthe nucleus area, the inner catheter control element 19 can be withdrawnby removing its distal connection to the junction point with the outercatheter element 12 or its distal connection with the distal innerexpansile loop, and pulling the inner catheter control element 19 out ofthe expansile loop. Alternatively, the inner catheter control element orfilament 19 may be cut off at its entry point into the expansile loopusing a surgical tool. This leaves a complete toroid, without defect,formed of the expansile loop in place to act as an annular reinforcementor replacement and/or nucleus reinforcement or replacement. It alsoallows the annular area of the device on the periphery and the nucleusportion of the device in the central region to have different physicalproperties dependent on the differential biocompatible materialsinjected into each region.

In an additional method of clinical use, once the nucleus of the dischas been removed, the present invention 10 is advanced into theinter-vertebral space. The braided expansile loop 24 is diametricallyexpanded in the manner previously described. The distal interior braidedexpansile loop 25 is pulled out of the outer expansile loop and theoverall expansile loop diametrically expands to the limits of the innerportion of the native annulus. Next the inner catheter control element19 is pulled back out of the expanded expansile loop and the innerpotion of the inner catheter or filament loop 19 pulls in the innercircumference of the expansile loop, making the central hole smaller andthe braided expansile loop 48 transversely wider to better fill thecentral defect in the vertebral space. This expanded braided expansileloop 48 may be used to contact a central prosthetic nucleus previouslyplaced in the middle of the braided expansile loop. In the case where noadditional nucleus prosthesis is desired, the central portion of thebraided expansile loop can be been expanded to the point whereessentially no central hole 37 remains in the toroid. The fully expandedbraided expansile loop can now be injected with a suitable biocompatiblematerial (as described above) which will expand or cure in situ aspreviously described. In this case the present invention will functionas both a prosthetic annulus and a prosthetic nucleus and its loadbearing properties will be dependent on the properties of the polymerchosen to fill the expansile loop.

Additionally, a hydrogel, polymer or biocompatible material may beinjected into the interior chamber of the expansile loop such that thebiocompatible material has the capacity to swell or increase in size asthe result of absorbing water or liquid. This would result in furtherexpansion of the expansile braided loop and an increase in theinter-vertebral disc height.

In another method of clinical use, the intended treatment is to fuse twoadjacent vertebrae using the present invention 10. Again using theillustration in FIG. 10, the end of the inner catheter control element19 is attached to the interior and distal end 22 of the braidedexpansile loop 24. To expand the diameter of the expansile loop onemerely needs to stabilize the proximal portion or outer end 23 of thebraided expansile loop and pull back the inner catheter control elementor filament 19 or wire. This will result in the inner section of thebraided expansile loop pulling out of the outer section of the braidedexpansile spiral as the wire is retracted. Once the desired outerdiameter of the braided expansile loop 48 is achieved, the centralportion of the braided expansile loop 48 may be contacted by pulling thesame inner catheter control element 19 further back out of the proximalportion of the braided expansile loop. The inner loop portion of theinner catheter control element or filament 19 will contract in diameterand pull on the inner circumference of the braided expansile loop 48resulting in the central “hole” of the toroid becoming smaller andsmaller in diameter 37. This results in the transverse diameter of thetoroid becoming bigger while the outer diameter stays the same. Once thedesired size is reached, the wire may be held in place and a polymericor other biologically compatible material as describe above injectedinto the toroid either through the inner catheter control element whichmay be in the form of a hollow catheter or hypotube, or alternativelyvia a catheter which is advanced into the toroid along the innercatheter control element or filament 19 or separately using a catheteror needle for injection. The fully expanded expansile loop 48 can now beinjected or filled with a suitable material for fusing the two adjacentvertebrae together. Candidates for a suitable fusing material include,but are not limited to, bond graft materials such as any described “bonecements” or any polymeric bone graft compounds, bone graft materials,nylon fibers, carbon fibers, glass fibers, collagen fibers, ceramicfibers, polyethylene fibers, poly(ethylene terephthalate),polyglycolides, polylactides, and combinations thereof.

Once the bone fusing material has been injected the inner cathetercontrol element 19 may be removed by retracting it from the braidedexpansile loop. Alternatively, the inner catheter control element 19 maybe cut off at its entrance point into the toroid. In another embodiment(not illustrated) the expansile loop may be expanded in diameter usingan inner filament of sufficient stiffness such as the metal wiredescribed and the central hole may be made smaller by pulling on aseparate flexible filament such as a thread attached to the inner radiusof the expansile braided.

In this embodiment of fusing two adjacent vertebrae together, it may bedesirable to stimulate growth of bone through the fill material. Tofacilitate bone integration and growth, the expansile loop should haveopenings that are more porous. The pores or openings of the expansileloop will have a diameter of about 0.25 mm to about 5.0 mm. The size isselected to allow tissue in-growth while containing the material packedinto the expansile loop. It is also contemplated that the expansile loopcan be seeded in vitro with bone forming cells, such as osteoblasts,and/or with growth factors. Multiple layers of osteoblast-seededapplications may be stacked on top of one another and further allowed toor encouraged to proliferate. In addition to in vitro seeding ofosteoblasts, other treatments for the braided expansile loop arecontemplated that also provide an implant that allows for bone in-growthand regeneration of bony tissue. For example, the expansile loop can becoated with a demineralized bone matrix or smeared or coated with anosteoinductive bone paste, such as OSTEOFIL™. In addition, the expansileloop can be coated with collagen, and subsequently soaked in apharmacological agent such as recombinant human bone morphogenicprotein, antibiotic agents, or other similar material.

An additional feature that can be incorporated to all of the embodimentsdisclosed herein is the means for attaching or securing the expansileloop or mesh 59, 60, 61, 62 to the surrounding disc structures, theannulus 36 and/or the native or artificial nucleus 34 or the vertebralendplates 35. One benefit of the described invention is that theattachment means 64 can secure the circumferential expansile loop ormesh 59, 60, 61, 62 to healthy tissue located away from a damaged areaor on the opposite side of the hernia or clinical entry site.

Shown in FIG. 23 is a cross sectional view of the attachment means 64 inthe from of a suture 66 and demonstrating a suture delivery system 68already advanced through an access tube 38 and utilizing non-absorbableor re-absorbable sutures 66 to attach the contracted configuration ofthe expansile mesh 59, 61 to the inner wall of the annulus 36 atmultiple points. Although not shown in FIG. 23, it is anticipated by theApplicants that the suture delivery system 68 can be used without theaccess tube 38 and can be advanced with or with the aid of endoscopethrough the access opening or potentially a hernia opening to performthe attachment procedure. Furthermore, other traditional surgical ormanipulation techniques not utilizing a delivery system 68 can be usedwith or without the aid of an endoscope through the access opening orpotentially a hernia opening to perform the attachment procedure.

The attachment means 64 for securing the expansile loop or mesh to theannulus 36 or native/artificial nucleus 34 could be through the use ofpreviously known technology such as sutures, clips, tacks, anchors,staples, screws, buttons, T-shaped tags, barbed tags, adhesives or othersimilar devices having appropriate securing characteristics. The term“attachment means” used herein encompasses sutures, clips, tacks,anchors, staples, screws, clamps, buttons, T-shaped tags, barbed tagsand other tissue holding means and delivery/manipulation techniques.

Whereby sutures 66 are known to be the standard in holding strength, theuse of tacks, staples and other fasteners continue to be developed andimplemented. Since the delivering, manipulating and retrieving a suture,often in a very tight surgical site is difficult the use and delivery ofnon-suture attachment means through a small opening to hold torn tissuehave been shown to have a clinical advantage.

FIG. 24 shows a cross sectional view of the attachment means 64 in theform of a staple or helicoil 70,71 with a delivery system 72 alreadyadvanced through the access tube 38 and utilizing non-absorbable orre-absorbable stables or helicoil mechanism 70 to secure the expandedexpansile mesh 60, 62 to the inner wall of the annulus 36 at multiplepoints. The staple or helicoil is being provided as an example in thisFigure since the attachment means 64 could be clips, tacks, anchors,staples, screws, clamps, buttons, T-shaped tags, barbed tags and othertissue holding means and delivery/manipulation techniques. Also shown inFIG. 24 is a cross sectional view of the a staple or helicoil deliverysystem 72 already advanced through the access tube 38 and utilizingnon-absorbable or re-absorbable stables or helicoils 71 to attach theexpanded expansile mesh 60, 62 to the outer wall of the native orartificial nucleus 34 at multiple points. Although not shown in FIG. 24,it is anticipated by the Applicants that the helicoil delivery system 72can be used without the access tube 38 and can be advanced with or withthe aid of an endoscope through the access opening or potentially ahernia opening to perform the attachment procedure. Furthermore, othertraditional surgical or manipulation techniques not utilizing a deliverysystem 72 can be used with or without the aid of an endoscope throughthe access opening or potentially a hernia opening to perform theattachment procedure.

The attachment means 64 is designed to engage the outer surface of theexpansile mesh and then engage the either the annulus 36 or the nucleus34, securing the expansile loop or mesh in place. Besides securing theexpansile mesh or loop in place, the use of an attachment means tosecure the expansile mesh or loop can facilitate the in-growth of newtissues.

The annulus/nucleus attachment means 64 could be installed within theexpansile mesh prior to insertion with the vertebral space. Alternatelythe annulus/nucleus attachment means 64 can be installed within theexpansile mesh after is inserted into the disc in a contactingconfiguration or after the mesh is expanded in the disc. Theannulus/nucleus attachment means 64 could be made from materials thatare biodegradable or bioabsorbable such as resorbable collagen, LPLA(poly(l-lactide)), DLPLA (poly(dl-lactide)), LPLA-DLPLA, PGA(polyglycolide), PGA-LPLA or PGA-DLPLA, polylactic acid and polyglycolicacid which is broken down and bioabsorbed by the patient over a periodof time.

Furthermore, as shown in FIG. 25, the expansile loop or mesh 60, 62could be expanded and secured to an endplate 35 a or 35 b or bothendplates 35 a and 35 b of the vertebral body. Also shown is annulartissue 36 sandwiched between the two vertebral endplates 35. Suchattachments means 64 are the same as the annulus 36 means but aredesigned for placement into hard bony tissues. This includes bonescrews, anchors, and other means 74 for attachment to hard tissue.

Attachment to the native nucleus could be required if a partialnuclectomy is performed. Attachment to an artificial nucleus 34 could beperformed following nuclectomy and placement of an artificial nucleus.Attachment of expansile mesh 60, 62 to the artificial nucleus 34 couldstabilize the artificial nucleus and/or maintain the artificialnucleus's position during delivery, during mesh expansion and over time.

Attachment of the expansile mesh 60, 62 to the annulus 36, native orartificial nucleus 34, or the endplates 35 could encourage in-growth ofbody tissues throughout the expansile mesh 60, 62 and therefore functionto reinforce and repair the annulus and strengthen the annulus ornucleus. Overall, the placement of the attachment means 64 into healthytissue will increase long-term stability.

One significant advantage of the described invention and attachmentmeans is that the attachment means may be placed into healthy annulartissue located distal to the annulectomy site or site of hernia defect.This is due to the complete circumferential nature of the expansile loopwithin the inner surface of the annulus. This is an advantage overpreviously described systems used to patch a hole created in the annulusin the area of a hernia defect or diseased tissue.

In addition, the expansile mesh 59, 60, 61, 62, can include materialsthat will act as a scaffold or carrier for delivering biologicmedicaments to vertebral tissues. The expansile mesh can be previouslytreated (for example, by soaking) with certain biologics (e.g. BMP,OP-1), or the access tube can be constructed to include a biologicdelivery means such that the biologic is 1) delivered while theattachment means 64 is being deployed, 2) delivered prior to deployingthe attachment means 64, 3) delivery subsequent to deploying theattachment means 64, or any combinations thereof.

It should be understood that the foregoing description of the presentinvention is intended merely to be illustrative thereof and that otherembodiments, modifications, and equivalents of the invention are withinthe scope of the invention recited in the claims appended hereto.Further, although each embodiment described above includes certainfeatures, the invention is not limited in this respect. Thus, one ormore of the above-described or other features of the invention, methodof delivery, or injection of biomaterial may be employed singularly orin any suitable combination, as the present invention is not limited toa specific embodiment.

1. A method for artificial disc replacement comprising the steps of:incorporating an attachment means within a flexible and expandableexpansile mesh, said expansile mesh having a control element and is heldin a contracted configuration; positioning said expansile mesh within anintervertebral space of a patient or animal; expanding said expansilemesh without pressurization, within said intervertebral space in asubstantially circumferential manner against the inner annular wall byuse of the control element acting directly on the mesh, the expandedexpansile mesh having a substantially continuous mesh loop configurationthat surrounds a disc nucleus; activating said attachment means wherebysaid attachment means substantially engages said expansile mesh toartificial or natural vertebral tissues.
 2. The method of claim 1wherein said attachment means comprises one or more staples.
 3. Themethod of claim 1 wherein said attachment means comprises one or moresutures.
 4. The method of claim 1 wherein said attachment meanscomprises one or more helicoils.
 5. The method of claim 1 wherein saidattachment means comprises one or more T-shaped clips or barbed T-shapedclips.
 6. The method of claim 1 wherein said vertebral tissues is one ormore endplates of the vertebrae.
 7. The method of claim 6 wherein saidattachment means comprises one or more screws.
 8. The method of claim 1wherein said vertebral tissues are native.
 9. The method of claim 1wherein said vertebral tissues are substantially native nucleus.
 10. Themethod of claim 1 wherein said vertebral tissues are substantiallyartificial nucleus.
 11. The method of claim 1 wherein said vertebraltissues are healthy tissues.
 12. The method of claim 1 wherein saidattachment means is re-absorbable or biodegradable.
 13. The method ofclaim 1, further comprising the step of delivering a biologic medicamentfrom said expansile mesh while said attachment means is being deployed.14. The method of claim 1, further comprising the step of delivering abiologic medicament from said expansile mesh prior to deploying saidattachment means.
 15. The method of claim 1, further comprising the stepof delivering a biologic medicament from said expansile mesh subsequentto deployment of said attachment means.
 16. The method of claim 1,further comprising the step of delivering a biologic medicament fromsaid expansile mesh over time after the surgical procedure.
 17. Themethod of claim 1, further comprising the step of delivering a biologicmedicament from an access opening while said attachment means is beingdeployed.
 18. The method of claim 1, further comprising the step ofdelivering a biologic medicament from an access opening prior todeploying said attachment means.
 19. The method of claim 1, furthercomprising the step of delivering a biologic medicament from an accessopening subsequent to deployment of said attachment means.
 20. A methodfor artificial disc replacement comprising the steps of: providing aflexible and expandable expansile mesh having a control element;positioning said expansile mesh while said mesh is in a contractedconfiguration within an intervertebral space of a patient or animal;incorporating an attachment means within said flexible and expandableexpansile mesh; expanding said expansile mesh without pressurizationwithin said intervertebral space in a substantially circumferentialmanner against the inner annular wall by use of the control elementacting directly on the mesh, the expanded mesh having a substantiallycontinuous mesh loop configuration that surrounds a disc nucleus;activating said attachment means whereby said attachment meanssubstantially engages said expansile mesh to artificial or naturalvertebral tissues.
 21. The method of claim 20 wherein said attachmentmeans comprises one or more staples.
 22. The method of claim 20 whereinsaid attachment means comprises one or more sutures.
 23. The method ofclaim 20 wherein said attachment means comprises one or more helicoils.24. The method of claim 20 wherein said attachment means comprises oneor more T-shaped clips or barbed T-shaped clips.
 25. The method of claim20 wherein said vertebral tissues is one or more endplates of thevertebrae.
 26. The method of claim 25 wherein said attachment meanscomprises one or more screws.
 27. The method of claim 1 wherein saidvertebral tissues are native.
 28. The method of claim 20 wherein saidvertebral tissues are substantially native nucleus.
 29. The method ofclaim 20 wherein said vertebral tissues are substantially artificialnucleus.
 30. The method of claim 20 wherein said vertebral tissues arehealthy tissues.
 31. The method of claim 20 wherein said attachmentmeans is re-absorbable or biodegradable.
 32. The method of claim 20,further comprising the step of delivering a biologic medicament fromsaid expansile mesh while said attachment means is being deployed. 33.The method of claim 20, further comprising the step of delivering abiologic medicament from said expansile mesh prior to deploying saidattachment means.
 34. The method of claim 20, further comprising thestep of delivering a biologic medicament from said expansile meshsubsequent to deployment of said attachment means.
 35. The method ofclaim 20, further comprising the step of delivering a biologicmedicament from an access opening while said attachment means is beingdeployed.
 36. The method of claim 20, further comprising the step ofdelivering a biologic medicament from an access opening prior todeploying said attachment means.
 37. The method of claim 20, furthercomprising the step of delivering a biologic medicament from an accessopening subsequent to deployment of said attachment means.
 38. Themethod of claim 20, further comprising the step of delivering a biologicmedicament from said expansile mesh over time after the surgicalprocedure.
 39. A method for artificial disc replacement comprising thesteps of: providing an expansile mesh having a control element;positioning said expansile mesh while said mesh is in a contractedconfiguration within an intervertebral space of a patient or animal;expanding said expansile mesh without pressurization within saidintervertebral space in a substantially circumferential manner againstthe inner annular wall by use of the control element acting directly onthe mesh, the expanded mesh having a substantially continuous mesh loopconfiguration that surrounds a disc nucleus; incorporating an attachmentmeans within the expanded expansile mesh; activating said attachmentmeans whereby said attachment means substantially engages said expansilemesh to artificial or natural vertebral tissues.
 40. The method of claim39 wherein said attachment means comprises one or more staples.
 41. Themethod of claim 39 wherein said attachment means comprises one or moresutures.
 42. The method of claim 39 wherein said attachment meanscomprises one or more helicoils.
 43. The method of claim 39 wherein saidattachment means comprises one or more T-shaped clips or barbed T-shapedclips.
 44. The method of claim 39 wherein said vertebral tissues is oneor more endplates of the vertebrae.
 45. The method of claim 44 whereinsaid attachment means comprises one or more screws.
 46. The method ofclaim 1 wherein said vertebral tissues are native.
 47. The method ofclaim 39 wherein said vertebral tissues are substantially nativenucleus.
 48. The method of claim 39 wherein said vertebral tissues aresubstantially artificial nucleus.
 49. The method of claim 39 whereinsaid vertebral tissues are healthy tissues.
 50. The method of claim 39wherein said attachment means is re-absorbable or biodegradable.
 51. Themethod of claim 39, further comprising the step of delivering a biologicmedicament from said expansile mesh while said attachment means is beingdeployed.
 52. The method of claim 39, further comprising the step ofdelivering a biologic medicament from said expansile mesh prior todeploying said attachment means.
 53. The method of claim 39, furthercomprising the step of delivering a biologic medicament from saidexpansile mesh subsequent to deployment of said attachment means. 54.The method of claim 39, further comprising the step of delivering abiologic medicament from an access opening while said attachment meansis being deployed.
 55. The method of claim 39, further comprising thestep of delivering a biologic medicament from an access opening prior todeploying said attachment means.
 56. The method of claim 39, furthercomprising the step of delivering a biologic medicament from an accessopening subsequent to deployment of said attachment means.
 57. Themethod of claim 39, further comprising the step of delivering a biologicmedicament from said expansile mesh over time after the surgicalprocedure.